Compilare: user.cpp: In function ‘int main()’: user.cpp:16:29: warning: suggest parentheses around comparison in operand of ‘^’ [-Wparentheses] if (xr[j] ^ xr[i-1] > best) { ^ user.cpp:10:11: warning: unused variable ‘x’ [-Wunused-variable] int n, x, best = 0 ; ^ user.cpp:8:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("xormax.in", "r", stdin); ^ user.cpp:9:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("xormax.out", "w", stdout); ^ user.cpp:12:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &n); ^ user.cpp:13:57: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] FOR (i,1,n) scanf ("%d", &a[i]),xr[i] = xr[i-1] ^ a[i]; ^